<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>盒子不同边框样式定义</title>
    <style>
        div{
            width: 200px;
            height: 200px;
            border-bottom: ridge 40px skyblue;   /* 边框底 */
            border-top:ridge 40px slateblue;    /* 边框顶 */
            border-left:ridge 40px slategray;     /* 边框左 */
            border-right:ridge 40px steelblue;       /* 边框右 */
            /* boder定义其他边框时需要写清楚样式，颜色，边框的宽度 ，同border简写*/
        }
    </style>
</head>
<body>
    <div></div>
</body>
</html>